Method and composition for ammoniation of soils



2,833,640 METHOD AND'COMPOSITION non p, r AMMONIATIONOF SOILS Frederick C. Bersworth, Framingham Center, Mass as signor to The Dow Chemilcal Company, 'Midlan'd, I

a corporation-Delaware v g No Drawing. Application Septembei'ltl, 1954 Serial No: 455,343 9 Claims, or. 71- 27 This invention relates to metho d"and composition forthe ammoniation of soils, and inparticular is concerned'with the application of certainpolynitrile compositions to soils-to bring; about conditions wherein a controlled liberation of ammonia occurs for fumig'ati'on of those'soils.

In many agriculturalestablishments it'has been'foundthat the repeated use of copper insecticides hadbroug'ht about a condition wherein an excess amount of copper is present in the soil as the inorganic compound used'as the insecticide. Generally no' seriousdeleterious effects result therefrom; However, when the soil is treated with certain ingredients, for "example ammonia; tok ill" on insect lifeharmful to the-rootsofthe plant's; 'or'tm supply needed ammonia to the 'soil; reaction between the ammoniaand copper occurs to form-complex copperammonia compounds, which thereby render copper availableto theplant and available in such concentration as to produce toxic effects. Also, where copper has beenliberally used as-an insecticide in certain ;areas,,the

toxicity shows in-the plants when fertilizers having! high,

nitrogenor'ammonia content areused. It is. accordingly a. fundamental object of the instanteinvention to provide agents, which, when applied to the soil, will permit a slow, controlled release of ammonia in the soil bywhicli the ammonia requirements of the soil can be satisfied without at the same time inducing the effects of copper axid'afithesame time to avoid the. increase in -the form'a' tion of copper ammonia; complexes.

ltx is 'aanothenobjecti oft the: invention to aprovide a composition w-useful for" solubilizing the: insoluble' inofi --ganic-" metal compoun'ds found in -soils.' 1

-O ther objects and advantages of: the invention" will:v in part. beiobviousnand in partappear hereinafter.

The-invention.aocordinglyis based uponthe method of. bringingabout a -control-led release of ammonia in soiliand'the 'solubilizat'ion of insoluble metal compounds, and a composition for somdoing'which is characterizedf by the i application to" tlie' soil in which" the plant is grow in'gof a composition c'ontaining a' con'rpoundcorresponding"to'ftlie"followinggeneral formula? 'B A V V I The mechanism by which these nitrile compounds func p p tion as they are applied to the soil andihydroly zed by t Q 60 moisture in the soil may be represented substantiallyas wherein -X-is'* an alkyle'ne group -which 'contributes two: follows: V

noonrom CHECN noornomomeoorr n-cnronms moment-N +NH; NCC 1-: men" not: 2 onion" noomcm omcoon noomonl ouio'o'on 'NBH- I I N-emom-N --omoH,-N +Nur noooca'i" ontooorr Noon. c'mo'oon to three carbon atoms to the chain, such as ethylene, isopropylene, trimethylene, 2,3-butylene, cyelohexylenef R is chosen from the group consisting of methylene, ethylene, isopropylene, trimethylene, and is, preferably. methylene; and A is chosen from the group consisting 0f CH COOM, Cl-I CH OH or longer chain fl-hydroxy 'alkyl' group, M being hydrogen, alkali metal on ammonium, and B may be A or RCN. In a -variation of the composition it may be mixed with about' one percent to fifty percent by weight of ethylenejdiamine -tetraacetic acid; ethanolethylenediamine tr'iaceti'c" acid;

' dietha'nolethylenediamine diacetic acid. The fullico riposition may include any organid'or'in'organic carrier,

the organic carriers being fertilizer materials, humus, compost, garbage and sewage residues, peat moss, and

the inorganie carriers being inorganic chemical fertilizers, ine'rt materials such as sand, vermiculite, lime; calcium phosphate or ground phosphate rock and similar minera fillers. Various other nitriles having similar structuralentities in the molecules may be" used, but for purposes of this invention those nitriles are' preferred which are characterized by containing a plurality of nitrile groups appropriately disposed with reference to one another so that upon hydrolysis they not only'give ammonia, but

they also generate compounds having a structurewhich 1 is characteristic of a very effective class off-clielating.

agents. For example, with an agent such 'aslethairiol ethylenediamine tri-methylenenitrile, one orniore of he nitrile groups can be present inthe' partial or coiiipl e? ly hydrolyzed form so that" all hydrolysis products up to and including the tri-acid or salts of the a'cid'niaylbe present. The presence of such acids or salts, whicliaiei chelating agents, gives in the presence of moisture and metal: ions, the metal chelate ofthe metahwhichfofms the most stable chelate. If, for example, copper, zinc andferric ironare present,- the ferric ironU-willbe, preferentially chelated; This new soluble'form; of; iron will then be available and valuable for mainta-ining and satisfying the nutritional requirements of the plantjforiron. Experience indicates that the preferentialchelation ofthe iron occurs most effectively in-acid soils.

Accordingly, the organiccompounds of -the nitrilej family of the type herein described function in a; dual capacity in that they provide for controlled release of ammonia andelimination, under proper conditions, of trace metal deficiencies, for example, iron. 'lI he com-.

' pounds in accordance with'the invention maybe applied directly by broadcasting on the soil followed by a diskingio fthe soil to work them beneath the surface, or they can be applied to the soil in a carrier which may} be functional, such as a fertilizer, or 'aninert carrier such as. sand, so that they are available for hydrolysis in the soil. ,7 Generally it is preferable to use a functional carrier such as phosphate rock, for the mixture ofcoin pounds added thereto not only renders calciumavailable to the plants, but also releases phosphoric 'acid andmakes it available,

2,833,640, Patented May 6,v 19 58 applied to the soil. 1

I the soil, but also to be available to the plantfor satisfac tion of nutritional requirements,

. 1 he residual compound left in'the: soil after hydrolysis.

of the nitrile group carries structural entities such that complex compounds with metal ions are formed. there by diminishing the possible toxic effect. At the same time, metalsin the soil in insoluble inorganic form are brought into. a complex form and as such a minute trace, of metal is made available in the soil for assimilation by' the plant.

Examples of specific compositions which can behm'adc' in accordance with this invention and applied to the soil to obtain the effects desired are as follows:

i I i Example I i A nitrogenous organicfertilizer, dried toremove moisture to a level below about percent, was blended with 5 percent by weight of ethanolethylenediamine triacetonitrile, Application to the soil, in usual quantities as determined by the fertilizerrequirements, makes theamount of fertilizer used'about one pound to square feet, so thatabout 5 pound per 10 square feet-of the nitrile is Example 2 When'th e compound is incorporated into a bulk soil conditioning agent such as the acryl'onitrile soil conditioning materials, a modified application results. Ethanolethy lenedia rnine.triacetonitrile is blended With the acrylonitrile conditioner in a proportion such that about pound to about ei pound per square foot ofthe soilis applied. Example 3 Ordinary sand of about the grade used for forming mortar mixes is blended with ethanolethylenediamine triacetonitrile and the mixture then applied to the soil and worked in. The ratio in which the acetonitrile'may be blendedwith theT-sand may be varied to-suit the convenience of the commercial operation involved. Generalf ly, however, a dilution of at least one part. of sand to one part of the acetonitrile is desirable, because it then becomes easier to control the exact rate of application of the compoundto the'soil. i

Example 4 j Compositions corresponding to those described in Examples 1 -3 are made up including an amount of polycarboxylic acid corresponding to the nitrile used. The preferredpolycarboxylic acid is that which is the end product of the hydrolysis of the nitrile. Thus the formulations become p i i Parts wgt; (1) Organic fertilizer 80-90 Ethanolethylenediamine triacetonitrile' 105 Ethanolethylenediamine triacetic acid, sodium Salt Iii-=5 (2) Soil conditioning agent L 50-90 Ethanolethylenediamine triacetonitrile 25-S Ethanolethylenediamine triacetic acid, sodium salt 25-5 (3) Sand 50 Ethanol'ethylenediamine triacetonitrile 25 i Ethanolethylenediamine triacetic acid, sodium salt M In those compositions where the acid or salt corresponding to the end product of hydrolysis is used, a solu- It is possible to use the nitrile, and its hydrolysis products in any degree. That is, a mixture of the tetra nitrile, trinitrile-monoacid, dinitrile-diacid, mononitrile-triacid, and tetra acid may be applied to the soil. Also the particular polycarboxylic acid used need not correspond to the final hydrolysis product; thus the tetraacetonitrile may be mixed with,ethanolethylenediamine, triacetic acid or the ethanolethylenediamine acetonitriles may be mixed with ethylenediamine tetraacetic acid.

In each instance, the material applied to the soil was Worked in by cultivating or disking in conventional style.

Over the weeks immediately following the application,

. normal rainfall provided moisture for hydrolysis of the bilizing eifect on the metal compounds in the soil is W brought about substantially immediately upon applic'ation. The effect of thechelating agent in the soil is prolonged by the presence of thenitrile which gradually.-

hydrolyzes to form the free acid.

nitrile and a gradual fumigation of the soil was obtained. The effect lasts substantially through a three to four month growing season. a

In one case several test areas of acre each were laid out in a field planted with celery which was showing serious copper toxicity. Application of the nitriles as set forth above produced within two weeks a noticeable improvement in the condition of the plants. That is, ammonia released became available slowly to the plants; the chelating agents formed in the hydrolysis reacted with copper in the soil to render it essentially unavailable to the plants. Where the plants show copper toxicity, the phenomenonis often called copper induced chlorosis, the application of the nitrile as described is particularly eificacious because copper catalyzes the hydrolysis of the nitrile. Hence, in the soil the nitrile is hydrolyzed at a rate accelerated by the copper to yield ammonia and a chelating agent. As hydrolyzed the chelating agent reacts with copper in the soil and binds it in non-ionic form.

.In general, it is found that the leaves from chlorotic trees and plants have a low iron content and are otherwise like chlorotic citrus leaves grown in calcareous soil.

It is apparent that the disorder is due to a soil condition which reduces the iron uptake of the plant. 'High concentrations of such metals as zinc, manganese and in particular copper are known to produce iron chlorosis symptoms in plants.

It is not unusual in an established citrus grove to find a very high concentration in the top soil, that is, the top 6-inch layer, of 30 to 50 parts per million of copper. Substantially smaller amounts are found in young groves and very minute traces only in virgin soils; that is, they will contain less than one part per million.

In general, it may be said that in an acid soil, substantial chlorosis will occur when the total copper content.

of the soil approaches about to 200 parts per million, which 'figure indicates about 300 pounds per acre per 6 inches. The copper chlorosis may be reduced and substantially eliminated by the treatment describedherein.

When the nitriles are applied to the soil, several. elfects are detected. Even though the total quantity of nitrile applied may be extremely small, the quantity will be large enough to develop a certain degree of toxicity to bacteria or other micro-organisms. The organic nitriles generally are fairly efiective fungicides and also organic nitriles are toxic to animal life in general. This toxicity is readily understandable since the nitriles are organic analogues of inorganic cyanides. Accordingly, when the ethylenediamine tetra nitrile is applied to soil, a very small amount will dissolve in moisture in the soil. Such nitrile, of course, develops physiological activity toward organisms ing organisms in the medium.

The specific examples are given in terms of results obpropylene diamine acetonitrile and the corresponding propionic nitriles, as, well as the diethanol. This is because the structure of the compound formed upon hydrolysis of age-agate eand six member rings-with'niet lsrimthe soil mediumgias fol-lowsin which Me is a polyvalent metal.

of the crude'reaction' prodiict olitained by partial con-- 2 version of etlfylelid'diami'fi. to.ethaiiol'tethylene diamine .itriacetonitrileand also the crude. reaction product/ oba e ffi bi if ms h tien,g fst s mage.

'formaldehyde and alkali'metal cyanide (i. e., inaaccordance 'with my UISI'Patent 2,407,645); The crude nitrile and polycarboxylic acid may be sprayed directlyiont o The composition for use with the carrier may be pre I pared directly from ethylene diamine. By reaction'of ethylene diamine with HCN and formaldehyde, the tetraacetonitrile may be formed. The ethanol ethylene diamines are formed readily by reaction with ethylene oxide.

in accordance with the following scheme:

with formaldehyde and HCN. When HCN absorption is about complete the reaction mixture is heated to about 60 C. for 2-3 hours. The synthesis maybe represented substantially as follows:

noomom H N-cmcmN f H/ n HCN HCHO i .HOCHaCHz CHICN N-CHaCHr-N N00 2 omoN as such, but the reaction mass is merely spray dried.v It

is also possible to dry the reaction product and simultaneously mix it with the carrier by spraying the solution directly onto the heated comminuted carrier.

Since the polycarboxylicamino acids are capable of dissolving inorganic metal compounds of any degree of insolubility and they are not metabolized, the general rule for their use in accordance with this invention is to use anionic constituents of the normally insoluble mineral.

of ethylene oxide the diethanol an amount of nitrile, or mixture of nitn'le and polycar- Example 5 Parts I weight Phosphate rock (approx: Ca (PO 50 Ethylenediamine tetra acetonitrile mixture 2S Ethylenediamine tetra acetic acid, sodium salt 25 The mixture of nitrileand ethylene diamine tetra acetic acid may be made up as such or it may be in the form the corresponding weight of phosphate rock ground to about 10-100 mesh. By heating the rock to about C. and spraying the hot solution thereon, a partial ,solubilization occurs in situvand a phosphate rock which will show an appreciable amount of free phosphoric acid is obtained.

The addition of polyamino polycarboxylic acids and/ or salts .to such minerals activate both the cationic and This action increases the availability of both trace metals and the P 0 portion of the phosphate rock.

"Though the invention has been described with reference to only a limited number of examples, it will be understood that variations thereof may be made without departing from the scope thereof. 3

Whatis claimed is:

1. A composition for application to soil to induce ammoniation thereof comprising, a solid carrier blended,

longer chain low molecular weight p-hydroxy alkyl: groups; B is selected from the group consisting of A,

CH COOM, and -RCN; and M is selectedfrom the group consisting of hydrogen, alkali metal and ammonium.

2. The composition in accordance with claim 1, in

which the carrier is sand.

3. The composition in accordance with claim 1, in which the carrier is a fertilizer having a moisture content not exceeding '5 percent.

4. The composition in accordance with claim 1, in which the carrier is inorganic material. I

5. The composition in accordance with claim 1, in which the carrier is an organic material.

6. The composition in accordance with claim which the carrier is phosphate rock. I

'7. A composition in accordance with claim 6, containing about 1 percent to about 50 percent of the'said compound blended with the said phosphate rock.

'8. The method of ammoniating soil, which comprises applying directly to the soil a composition characterized by its containing a compound corresponding to the following general formula:

NCR RON wherein X is analkylene group whichinterposes two to three carbon atoms in the chain between the indicated nitrogen atoms; R is chosen from the group consistingof methylene, ethylene, isopropylene, trimethylene; A is selected from the group consisting of CH CH OH, and

longer chain low molecular weight fi-hydroxy alkyl groups; B is selected from the group consisting of A, --CH COOM and RC N; and M is selected from the group consisting of hydrogen alkali metal and ammonium, and working said' composition into the soil.

9. The method in accordance with claim 8, in which the composition is contained in a solid carrier;

(References on following page) v "7 V s l lef e repceg th e file, of this patent V v OTHER REFERENCES I L UNITEDSTATES'VPATENTS H Plant Physiology, Jacobson, Maintenanc'eo'of :Iro'n Sup- '995 J Y mic 0; ply in Nut rient Solutions-Addition of Ferric Potassium e 1 A ricultu ral Chem. Alexander et a1. Control of Iron 2,407,645 1 Se t. 17; 1946 g 7 2,498,480 Bierlich Feb? 21, "1950 h my H n 7 3 a Sexence, Stewart etal. Chelates as Source of Iron for Plants, November 21', 1952,pages 564-:66. 

1. A COMPOSITION FOR APPLICATION TO SOIL TO INDUCE AMMONIATION THEREOF COMPRISING, A SOLID CARRIER BLENDED WITH A COMPOUND HAVING THE FOLLOWING GENERAL FORMULA: 